Experimental Design: Treatments, Control, Randomization, and Replication
Experimental Design: Treatments, Control, Randomization, and Replication practice bank: Solve the visible multiple-choice and free-response questions, then compare every step with the worked answers.
Experimental Design: Treatments, Control, Randomization, and Replication: formulas and targets
| Random assignment | Supports causal inference. |
|---|---|
| Random sampling | Supports population generalization. |
Experimental Design multiple-choice practice
Question 1. Experimental Design
A public high school in Pine Ridge during a quarterly performance study will compare two programs affecting algebra benchmark completion. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: B
At the public high school in Pine Ridge during a quarterly performance study, group the students by age group, then randomly assign units within each block to the two programs affecting algebra benchmark completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 2. Experimental Design
A housing authority in Westview during a randomized pilot period will compare two programs affecting application processing time. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: A
At the housing authority in Westview during a randomized pilot period, group the applications by previous experience, then randomly assign units within each block to the two programs affecting application processing time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 3. Experimental Design
A housing authority in Pine Ridge during a service-improvement study will compare two programs affecting application processing time. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: C
At the housing authority in Pine Ridge during a service-improvement study, group the applications by baseline score, then randomly assign units within each block to the two programs affecting application processing time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 4. Experimental Design
A community college in Great Lakes during a service-improvement study will compare two programs affecting course completion. Describe a randomized design that uses site as a block and explain the benefit.
Answer: D
At the community college in Great Lakes during a service-improvement study, group the enrolled learners by site, then randomly assign units within each block to the two programs affecting course completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 5. Experimental Design
A regional hospital in Central County during a summer implementation review will compare two programs affecting appointment completion. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: C
At the regional hospital in Central County during a summer implementation review, group the patients by age group, then randomly assign units within each block to the two programs affecting appointment completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 6. Experimental Design
A state park in Metro East during a winter readiness review will compare two programs affecting trail-use duration. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: C
At the state park in Metro East during a winter readiness review, group the visitors by age group, then randomly assign units within each block to the two programs affecting trail-use duration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 7. Experimental Design
A regional hospital in Pine Ridge during a fall 2026 audit will compare two programs affecting appointment completion. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: A
At the regional hospital in Pine Ridge during a fall 2026 audit, group the patients by previous experience, then randomly assign units within each block to the two programs affecting appointment completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 8. Experimental Design
A state park in Atlantic Corridor during a yearly program evaluation will compare two programs affecting trail-use duration. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: C
At the state park in Atlantic Corridor during a yearly program evaluation, group the visitors by previous experience, then randomly assign units within each block to the two programs affecting trail-use duration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 9. Experimental Design
A county election office in Great Lakes during a spring 2027 pilot will compare two programs affecting ballot-processing time. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: A
At the county election office in Great Lakes during a spring 2027 pilot, group the ballots by baseline score, then randomly assign units within each block to the two programs affecting ballot-processing time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 10. Experimental Design
A grocery cooperative in Cedar Grove during a regional benchmarking study will compare two programs affecting checkout time. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: D
At the grocery cooperative in Cedar Grove during a regional benchmarking study, group the customers by baseline score, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 11. Experimental Design
A grocery cooperative in North Valley during a semester-long cohort study will compare two programs affecting checkout time. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: D
At the grocery cooperative in North Valley during a semester-long cohort study, group the customers by age group, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 12. Experimental Design
A city transit agency in Riverbend during a community outreach cycle will compare two programs affecting on-time arrival. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: A
At the city transit agency in Riverbend during a community outreach cycle, group the bus trips by baseline score, then randomly assign units within each block to the two programs affecting on-time arrival. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 13. Experimental Design
A county library in Midwest consortium during a school-year data collection will compare two programs affecting weekly program attendance. Describe a randomized design that uses site as a block and explain the benefit.
Answer: D
At the county library in Midwest consortium during a school-year data collection, group the visitors by site, then randomly assign units within each block to the two programs affecting weekly program attendance. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 14. Experimental Design
A city recreation department in Pacific Northwest during a six-week field trial will compare two programs affecting program satisfaction. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: A
At the city recreation department in Pacific Northwest during a six-week field trial, group the participants by age group, then randomly assign units within each block to the two programs affecting program satisfaction. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 15. Experimental Design
A housing authority in Lakeside district during a quarterly performance study will compare two programs affecting application processing time. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: C
At the housing authority in Lakeside district during a quarterly performance study, group the applications by age group, then randomly assign units within each block to the two programs affecting application processing time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 16. Experimental Design
A digital learning platform in South Harbor during a semester-long cohort study will compare two programs affecting lesson completion. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: D
At the digital learning platform in South Harbor during a semester-long cohort study, group the learners by age group, then randomly assign units within each block to the two programs affecting lesson completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 17. Experimental Design
A regional manufacturer in Central County during a multiweek validation study will compare two programs affecting part diameter. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: A
At the regional manufacturer in Central County during a multiweek validation study, group the parts by age group, then randomly assign units within each block to the two programs affecting part diameter. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 18. Experimental Design
A housing authority in Sunbelt district during a monthly quality review will compare two programs affecting application processing time. Describe a randomized design that uses site as a block and explain the benefit.
Answer: D
At the housing authority in Sunbelt district during a monthly quality review, group the applications by site, then randomly assign units within each block to the two programs affecting application processing time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 19. Experimental Design
A school district in Great Lakes during a semester-long cohort study will compare two programs affecting lunch-program participation. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: B
At the school district in Great Lakes during a semester-long cohort study, group the students by baseline score, then randomly assign units within each block to the two programs affecting lunch-program participation. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 20. Experimental Design
A state park in New England network during a quarterly performance study will compare two programs affecting trail-use duration. Describe a randomized design that uses site as a block and explain the benefit.
Answer: D
At the state park in New England network during a quarterly performance study, group the visitors by site, then randomly assign units within each block to the two programs affecting trail-use duration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 21. Experimental Design
A city transit agency in Pine Ridge during a regional benchmarking study will compare two programs affecting on-time arrival. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: A
At the city transit agency in Pine Ridge during a regional benchmarking study, group the bus trips by previous experience, then randomly assign units within each block to the two programs affecting on-time arrival. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 22. Experimental Design
A regional manufacturer in Pine Ridge during a multiweek validation study will compare two programs affecting part diameter. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: A
At the regional manufacturer in Pine Ridge during a multiweek validation study, group the parts by baseline score, then randomly assign units within each block to the two programs affecting part diameter. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 23. Experimental Design
A university advising center in Prairie District during a baseline measurement week will compare two programs affecting appointment wait time. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: C
At the university advising center in Prairie District during a baseline measurement week, group the appointments by age group, then randomly assign units within each block to the two programs affecting appointment wait time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 24. Experimental Design
A grocery cooperative in Pine Ridge during a monthly quality review will compare two programs affecting checkout time. Describe a randomized design that uses site as a block and explain the benefit.
Answer: B
At the grocery cooperative in Pine Ridge during a monthly quality review, group the customers by site, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 25. Experimental Design
A municipal water office in Cedar Grove during a semester-long cohort study will compare two programs affecting monthly household use. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: C
At the municipal water office in Cedar Grove during a semester-long cohort study, group the accounts by baseline score, then randomly assign units within each block to the two programs affecting monthly household use. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 26. Experimental Design
A grocery cooperative in Cedar Grove during a yearly program evaluation will compare two programs affecting checkout time. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: C
At the grocery cooperative in Cedar Grove during a yearly program evaluation, group the customers by previous experience, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 27. Experimental Design
A public high school in Sunbelt district during a multiweek validation study will compare two programs affecting algebra benchmark completion. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: A
At the public high school in Sunbelt district during a multiweek validation study, group the students by age group, then randomly assign units within each block to the two programs affecting algebra benchmark completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 28. Experimental Design
A county library in Midwest consortium during a baseline measurement week will compare two programs affecting weekly program attendance. Describe a randomized design that uses site as a block and explain the benefit.
Answer: C
At the county library in Midwest consortium during a baseline measurement week, group the visitors by site, then randomly assign units within each block to the two programs affecting weekly program attendance. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 29. Experimental Design
A regional hospital in Mountain Region during a spring 2027 pilot will compare two programs affecting appointment completion. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: B
At the regional hospital in Mountain Region during a spring 2027 pilot, group the patients by baseline score, then randomly assign units within each block to the two programs affecting appointment completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 30. Experimental Design
A recycling program in Westview during a community outreach cycle will compare two programs affecting weekly material weight. Describe a randomized design that uses age group as a block and explain the benefit.
Answer: B
At the recycling program in Westview during a community outreach cycle, group the households by age group, then randomly assign units within each block to the two programs affecting weekly material weight. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by age group, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 31. Experimental Design
A grocery cooperative in Capital Region during a community outreach cycle will compare two programs affecting checkout time. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: A
At the grocery cooperative in Capital Region during a community outreach cycle, group the customers by previous experience, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 32. Experimental Design
A municipal emergency dispatch center in Cedar Grove during a school-year data collection will compare two programs affecting response time. Describe a randomized design that uses site as a block and explain the benefit.
Answer: C
At the municipal emergency dispatch center in Cedar Grove during a school-year data collection, group the calls by site, then randomly assign units within each block to the two programs affecting response time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 33. Experimental Design
A public high school in Coastal Plains during a six-week field trial will compare two programs affecting algebra benchmark completion. Describe a randomized design that uses previous experience as a block and explain the benefit.
Answer: D
At the public high school in Coastal Plains during a six-week field trial, group the students by previous experience, then randomly assign units within each block to the two programs affecting algebra benchmark completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice B: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by previous experience, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 34. Experimental Design
A state park in Central County during a spring 2027 pilot will compare two programs affecting trail-use duration. Describe a randomized design that uses baseline score as a block and explain the benefit.
Answer: B
At the state park in Central County during a spring 2027 pilot, group the visitors by baseline score, then randomly assign units within each block to the two programs affecting trail-use duration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by baseline score, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 35. Experimental Design
A regional airport authority in New England network during a follow-up evaluation period will compare two programs affecting security wait time. Describe a randomized design that uses site as a block and explain the benefit.
Answer: B
At the regional airport authority in New England network during a follow-up evaluation period, group the travelers by site, then randomly assign units within each block to the two programs affecting security wait time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Question 36. Experimental Design
A food safety laboratory in Prairie District during a summer implementation review will compare two programs affecting sample concentration. Describe a randomized design that uses site as a block and explain the benefit.
Answer: B
At the food safety laboratory in Prairie District during a summer implementation review, group the samples by site, then randomly assign units within each block to the two programs affecting sample concentration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
Why the other choices fail
- Choice A: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice C: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
- Choice D: It does not match the requested calculation. The correct comparison or result is: Block by site, randomize treatments within each block, and compare responses; this controls block-to-block variation. Key check: Random assignment supports cause-and-effect conclusions for the experimental units.
Experimental Design free-response practice
| Evidence | Points |
|---|---|
| Correct target, notation, direction, or group order | 2 |
| Correct method/model and defensible conditions | 2 |
| Correct setup and execution | 3 |
| Contextual interpretation and scope/limitation | 2 |
| Clear communication with units and labels | 1 |
FRQ set 1: Experimental Design
Scenario. A community bank in Midwest consortium during a multiweek validation study will compare two programs affecting mobile-deposit adoption. Describe a randomized design that uses baseline score as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the community bank in Midwest consortium during a multiweek validation study, group the customers by baseline score, then randomly assign units within each block to the two programs affecting mobile-deposit adoption. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 2: Experimental Design
Scenario. A solar installer in Desert County during a monthly quality review will compare two programs affecting daily energy output. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the solar installer in Desert County during a monthly quality review, group the installations by site, then randomly assign units within each block to the two programs affecting daily energy output. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 3: Experimental Design
Scenario. A city recreation department in Pine Ridge during a semester-long cohort study will compare two programs affecting program satisfaction. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the city recreation department in Pine Ridge during a semester-long cohort study, group the participants by site, then randomly assign units within each block to the two programs affecting program satisfaction. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 4: Experimental Design
Scenario. A grocery cooperative in Prairie District during a two-month observation window will compare two programs affecting checkout time. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the grocery cooperative in Prairie District during a two-month observation window, group the customers by site, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 5: Experimental Design
Scenario. A farm cooperative in Great Lakes during a fall 2026 audit will compare two programs affecting crop yield. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the farm cooperative in Great Lakes during a fall 2026 audit, group the plots by site, then randomly assign units within each block to the two programs affecting crop yield. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 6: Experimental Design
Scenario. A grocery cooperative in Cedar Grove during a school-year data collection will compare two programs affecting checkout time. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the grocery cooperative in Cedar Grove during a school-year data collection, group the customers by site, then randomly assign units within each block to the two programs affecting checkout time. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 7: Experimental Design
Scenario. A recycling program in Central County during a monthly quality review will compare two programs affecting weekly material weight. Describe a randomized design that uses baseline score as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the recycling program in Central County during a monthly quality review, group the households by baseline score, then randomly assign units within each block to the two programs affecting weekly material weight. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 8: Experimental Design
Scenario. A solar installer in Pacific Northwest during a six-week field trial will compare two programs affecting daily energy output. Describe a randomized design that uses age group as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the solar installer in Pacific Northwest during a six-week field trial, group the installations by age group, then randomly assign units within each block to the two programs affecting daily energy output. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 9: Experimental Design
Scenario. A food safety laboratory in New England network during a monthly quality review will compare two programs affecting sample concentration. Describe a randomized design that uses age group as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the food safety laboratory in New England network during a monthly quality review, group the samples by age group, then randomly assign units within each block to the two programs affecting sample concentration. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with age group, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 10: Experimental Design
Scenario. A city recreation department in Central County during a weekday operations study will compare two programs affecting program satisfaction. Describe a randomized design that uses previous experience as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the city recreation department in Central County during a weekday operations study, group the participants by previous experience, then randomly assign units within each block to the two programs affecting program satisfaction. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 11: Experimental Design
Scenario. A community college in Sunbelt district during a follow-up evaluation period will compare two programs affecting course completion. Describe a randomized design that uses previous experience as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the community college in Sunbelt district during a follow-up evaluation period, group the enrolled learners by previous experience, then randomly assign units within each block to the two programs affecting course completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with previous experience, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 12: Experimental Design
Scenario. A farm cooperative in Midwest consortium during a follow-up evaluation period will compare two programs affecting crop yield. Describe a randomized design that uses baseline score as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the farm cooperative in Midwest consortium during a follow-up evaluation period, group the plots by baseline score, then randomly assign units within each block to the two programs affecting crop yield. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 13: Experimental Design
Scenario. A farm cooperative in Atlantic Corridor during a quarterly performance study will compare two programs affecting crop yield. Describe a randomized design that uses baseline score as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the farm cooperative in Atlantic Corridor during a quarterly performance study, group the plots by baseline score, then randomly assign units within each block to the two programs affecting crop yield. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with baseline score, which can improve precision; random assignment supports a causal comparison for these experimental units.
FRQ set 14: Experimental Design
Scenario. A community college in Cedar Grove during a school-year data collection will compare two programs affecting course completion. Describe a randomized design that uses site as a block and explain the benefit.
- Identify the observational units, population, treatments or sampling frame, and the design goal.
- Describe the selection or assignment mechanism precisely enough that another researcher could implement it.
- Explain how the design controls bias, confounding, or variability, and identify a remaining limitation.
- State the scope of inference: population generalization, causal conclusion, both, or neither.
Model response
At the community college in Cedar Grove during a school-year data collection, group the enrolled learners by site, then randomly assign units within each block to the two programs affecting course completion. Keep other conditions as similar as practical and compare responses. Blocking controls variation associated with site, which can improve precision; random assignment supports a causal comparison for these experimental units.
